Citations

Abstract Purpose: Adolescents with chronic orthostatic intolerance (COI) experience symptoms related to impaired tolerance of upright posture. Postural Orthostatic Tachycardia Syndrome (POTS) is a specific type of COI, marked by an excessive increase in heart rate (≥40 bpm or an absolute HR >120 bpm) when standing. This study compares Functional Disability Inventory (FDI) scores between adolescents with COI with and without excessive postural tachycardia (POTS subtype). Methods: Patients ≤19 years referred to our POTS program (Aug 2024–Mar 2025) with orthostatic symptoms for>3 months were included. Based on active stand HR, patients were categorized as POTS (HR ≥40 bpm) or COI without excessive postural tachycardia (HR <40 bpm). FDI scores were collected. Chi-square tests assessed group differences. A two-sample t-test compared FDI severity. Linear regression evaluated the association between HR change and FDI score. Results: All data were normally distributed, allowing the use of parametric analyses. Of the 92 patients (46 per group), 78% were female. The mean age was 16.0 ± 1.48 years in the COI group and 16.3 ± 1.7 years in the POTS group, with no significant sex differences between groups. The COI group had a higher mean FDI score than the POTS group, but this difference was not statistically significant. The distribution of FDI severity (mild, moderate, severe) was similar between groups. Linear regression showed a non-significant trend of a 1 bpm increase in heart rate associated with a 0.1055-point decrease in FDI score Conclusion: Functional disability was similar between the COI and POTS groups.

Importance Tau positron emission tomography (PET) allows in vivo detection of neurofibrillary tangles, a core neuropathologic feature of Alzheimer disease (AD). Objective To provide estimates of the frequency of tau PET positivity and its associated risk of clinical outcomes. Design, Setting, and Participants Longitudinal study using data pooled from 21 cohorts, comprising a convenience sample of 6514 participants from 13 countries, collected between January 2013 and June 2024. Cognitively unimpaired individuals and patients with a clinical diagnosis of mild cognitive impairment (MCI), AD dementia, or other neurodegenerative disorders were included. Exposures Tau PET with flortaucipir F 18, amyloid-β (Aβ) PET, and clinical examinations. Tau PET scans were visually rated as positive according to a US Food and Drug Administration– and European Medicines Agency–approved method, designed to indicate the presence of advanced neurofibrillary tangle pathology (Braak stages V-VI). Main Outcomes and Measures Frequency of tau PET positivity and absolute risk of clinical progression (eg, progression to MCI or dementia). Results Among the 6514 participants (mean age, 69.5 years; 50.5% female), median follow-up time ranged from 1.5 to 4.0 years. Of 3487 cognitively unimpaired participants, 349 (9.8%) were tau PET positive; the estimated frequency of tau PET positivity was less than 1% in those aged younger than 50 years, and increased from 3% (95% CI, 2%-4%) at 60 years to 19% (95% CI, 16%-24%) at 90 years. Tau PET positivity frequency estimates increased across MCI and AD dementia clinical diagnoses (43% [95% CI, 41%-46%] and 79% [95% CI, 77%-82%] at 75 years, respectively). Most tau PET–positive individuals (92%) were also Aβ PET positive. Cognitively unimpaired participants who were positive for both Aβ PET and tau PET had a higher absolute risk of progression to MCI or dementia over the following 5 years (57% [95% CI, 45%-71%]) compared with both Aβ PET–positive/tau PET–negative (17% [95% CI, 13%-22%]) and Aβ PET–negative/tau PET–negative (6% [95% CI, 5%-8%]) individuals. Among participants with MCI at the time of the tau PET scan, an Aβ PET–positive/tau PET–positive profile was associated with a 5-year absolute risk of progression to dementia of 70% (95% CI, 59%-81%). Conclusions and Relevance In a large convenience sample, a positive tau PET scan occurred at a nonnegligible rate among cognitively unimpaired individuals, and the combination of Aβ PET positivity and tau PET positivity was associated with a high risk of clinical progression in both preclinical and symptomatic stages of AD. These findings underscore the potential of tau PET as a biomarker for staging AD pathology.

Objectives To compare electrical stimulation and speech perception in vestibular schwannoma (VS) patients across treatment modalities and standard cochlear implant (CI) patients. Study Design Retrospective review. Setting Tertiary academic center. Patients Sixty-seven CI ears consisting of 23 standard CI controls and 44 VS patients with ipsilateral CI. VS patients were separated by treatment modality: 24 microsurgical resection, 15 radiation therapy, and 5 observation. Eleven VS patients with CI did not receive auditory sensation from electrical stimulation. Interventions VS microsurgical resection, radiation therapy, and observation. Main Outcome Measures Threshold (T-levels), comfort (C-levels), consonant-nucleus-consonant (CNC) word score, and AzBio sentence recognition scores. Results Patients who underwent microsurgical resection required significantly higher (p < 0.001) T-levels and C-levels compared with the standard CI group. Stimulation levels in the VS radiation therapy and observation groups were higher but not significantly different compared with standard CI controls. Overall rate of CI nonstimulation across all VS patients was 25%: 38% for microsurgery and 13% for radiation. Average CNC score for microsurgery group was 18% compared with 44% for radiation, 55% for observation, and 68.5% for standard CI controls. CNC word and AzBio scores were significantly lower (p < 0.001) for the microsurgery group compared with standard CI group. Conclusions Resection may negatively affect auditory nerve function, leading to higher stimulation levels, increased risk of nonstimulation, and poorer postoperative CI speech outcomes compared with observation or radiosurgery. When medically appropriate, nonsurgical VS management may be used to allow for optimization of CI programming and postoperative hearing outcomes.

Abstract Neurofibrillary tangles are dynamic neuropathologic hallmarks of Alzheimer’s disease with a hypothesized lifespan morphologically-defined by three maturity levels: pretangles, mature tangles, and ghost tangles. To better understand the progression of tangle pathophysiology, we characterized tangle maturity level predilection of 15 tau antibodies recognizing a broad range of linear, phosphorylation, conformational, and truncation epitopes in the hippocampus of 24 postmortem brains. We developed the tangle maturity scoring system to semi-quantitatively evaluate each tangle maturity level. Based on proportions of tangle maturity levels, we classified antibodies as “early” (mostly pretangles and mature tangles), “middling” (mature tangles with pretangles and ghost tangles), and “advanced” (mostly ghost tangles and mature tangles) tangle maturity markers. To summarize tangle maturity predilection, we developed the tangle maturity scale to integrate individual tangle maturity scores. Correlations showed stronger relationships between tangle maturity scale and subsector thickness for more advanced tangle maturity markers in CA1 and subiculum, whereas Braak tangle stage remained consistently correlated throughout markers of the tangle lifespan. To aid in scoring hippocampi, we used machine learning to recognize tangle maturity levels, which performed comparably to a domain expert and showed similar relationships by Spearman correlation. Pattern recognition software was used to assess tangle and neuritic tau burden separately, which generally correlated with Braak stage and neuronal counts. However, tangle-derived tau burden more consistently correlated with hippocampal subsector thickness. In conclusion, we developed manual and automated scoring systems to evaluate tangle maturity levels, demonstrating early 4R, phosphorylated, and oligomeric tau accumulation preceding more advanced 3R and truncated tau. Our study provides supportive evidence of disease-relevant ordering of tau posttranslational modifications in the brain, which may have implications for theragnostic development. These findings underscore the promise of computerized quantitative analyses (i.e., pathomics) for high-throughput feature extraction from whole-slide images to enhance our understanding of microscopically observed morphologic changes.

ABSTRACT Background Kidney disease significantly increases the risk of dementia, including among kidney transplant (KTx) recipients. To date, the cost implications of dementia after KTx are not well described. Methods We performed a retrospective cohort study of US Renal Data System (USRDS) data (2006–2020) to estimate cost of care for ≥65‐year‐old Medicare insured KTx recipients (2006–2020) with newly diagnosed dementia ( n = 3285), compared to propensity‐matched controls without dementia ( n = 6570). KTx recipients age 65+ years with post‐KTx dementia were identified by diagnosis codes, and costs were computed based on payments on Medicare claims. Average costs per month, marginal costs per month, and cumulative costs were compared after dementia diagnosis versus after the equivalent time post‐KTx in controls. Results Dementia was diagnosed at a mean of 5.1 ± 3.4 years post‐KTx. Patients' characteristics were well matched in cases versus controls, including age (mean: 70.1 vs. 69.9 years), sex (38.4% vs. 37.9% women), race (23.7% vs. 22.2% African American), and cause of ESKD (45.4% vs. 43.7% diabetes). Over 4 years post‐KTx, dementia was associated with reduced survival (27% vs. 68%) along with $66 145 (95% CI $51 560‐$78 489) higher Medicare spending. Average monthly costs in dementia patients reached a maximum of $12 713 and exceeded the cost of unaffected patients by up to $9789 per month. Conclusions Post‐KTx dementia dramatically increased resource utilization and reduced post‐KTx surivival. These findings highlight the need for care pathways that better integrate cognitive health assessment and management into the care of KTx candidates and recipients.